Outerra forum

Anteworld - Outerra Game => Tech demo, support, updates => Topic started by: M7 on August 07, 2014, 10:34:26 am

Title: Reflectance question
Post by: M7 on August 07, 2014, 10:34:26 am
I'm trying to make sense of the reflectance map. So on this cube, i used an albedo, roughness and a reflectance map.

So what i can observe is that  reflectance map from 0.0 to 0.43 seems to be the full range of a regular specular map. (Im still confused as to how other 3d program call a reflectance map)

 Then over  about 0.43 , it's something else. It becomes a flat value where the albedo is back at 100% and the mirror effect stay full (as it pick up no shadows)

I'm asking cause i want to use specular maps from programs like Ddo (quixel suite). So for these to work as expected, i would have to set the F0 to 0.43 ? I'm sure i'm still missing something...

(http://i.imgur.com/ulxGfXu.jpg)
Title: Re: Reflectance question
Post by: 2eyed on August 07, 2014, 10:48:49 am
There is need  for someone doing documentation and updates therefor.
Title: Re: Reflectance question
Post by: angrypig on August 08, 2014, 11:04:57 am
I made update to our wiki page i hope it will help you.

http://xtrac.outerraworld.com/trac.fcgi/wiki/material (http://xtrac.outerraworld.com/trac.fcgi/wiki/material)
Title: Re: Reflectance question
Post by: M7 on August 08, 2014, 12:03:08 pm
Thanks Angrypig for the wiki update. It doesnt quite clarify the logic of reflectance (especially the break in the value at 0.43)  but just by asking the question, i  got a more clear idea of what i can do with that it. So i'll experiment so more.
Title: Re: Reflectance question
Post by: angrypig on August 08, 2014, 12:07:51 pm
There is condition if "f0 > 0.45" then the material is metallic. It will change in the future there will be additional value in the material definition "metallicity".
Title: Re: Reflectance question
Post by: ddenn on August 08, 2014, 12:35:58 pm
Maybe better to add additional texture to set "f0"? That way we can combine plastic/metallic parts in one material

P.s. Sorry, just read the wiki. Is reflectance map working already? I missed that somehow
P.p.s Yep, already working. Sorry )
Title: Re: Reflectance question
Post by: M7 on August 08, 2014, 03:02:52 pm
So yeah in order to use a reflectance map with tonal values, the F0 have to be set at 0.45 or lower

Here i tried to get some dirt on a chrome surface. Now if i set the F0 to 0.46 , the chrome start to turn  black like on the buttom right image.

(http://i.imgur.com/2RO6HXa.jpg)